A noose is a loop at the end of a rope in which the knot tightens under load and can be loosened without. The knot can be used to secure a rope to a post or pole, but only where the end is in a position that the loop can be passed over.

The knot most closely associated with execution is the hangman's knot, which is also known as the "hangman's noose." Tying is similar to the original noose, but several turns are wrapped around the loop. The reason for this was to make the hanging more "humane," as it would break the person's neck, killing them instantly, rather than strangling them to death.

In the US, a noose is sometimes left as a message in order to intimidate people. Its meaning is derived from its use in segregation eralynchings.[2][3][4]It is illegal to display a noose in a threatening manner in New York and Connecticut.[5]